The ligand-field density functional theory (LFDFT) approach is employed for calculations of the Co nuclear magnetic resonance (NMR) shielding tensor of all four diastereoisomers (kkk, kkd, kdd, and ddd) of tris(1,2ethanediamine) cobalt(III) complex ion, [Co(en)3] . The obtained values split into two groups according to the point group of the diastereoisomers. The influence of the individual rin...

The use of genetic algorithms for the optimisation of magic angle spinning NMR pulse sequences is discussed. The discussion uses as an example the optimisation of the C7(2)(1) dipolar recoupling pulse sequence, aiming to achieve improved efficiency for spin systems characterised by large chemical shielding anisotropies and/or small dipolar coupling interactions. The optimised pulse sequence is ...

Solid state 59Co nuclear magnetic resonance (NMR) spectra were recorded on diamagnetic complexes with general structure Co(Por)L2, where Por ) tetraphenylporphyrin, tetramethoxyphenylporphyrin, and octaethylporphyrin; and L ) imidazole, methylimidazole, pyridine, and isoquinoline. Measurements were carried out at different magnetic field strengths (4.7, 7.1, and 11.7 T) on both static and spinn...

We report solid-state 25Mg NMR, X-ray crystallographic, and quantum-mechanical calculation results for bis(pyridine)(5,10,15,20-tetraphenylporphyrinato)magnesium(II), Mg(TPP)·Py2. Mg(TPP)·Py2 crystallizes in the triclinic form, in the space group P1. The unit cell parameters are: a = 9.6139(13) Å, b = 11.0096(16) Å, c = 11.8656(15) Å; α = 102.063(3)°, β = 103.785(3)°, γ = 114.043(2)°; Z = 1. Th...

(51)V NMR parameters have been calculated for VOCl(3), the reference compound in (51)V NMR spectroscopy, in order to capture environmental effects in both the neat liquid and the solid state. Using a combination of periodic geometry optimizations and Car-Parrinello molecular dynamics simulations with embedded cluster NMR calculations, we are able to test the ability of current computational app...

The effect of rotation and vibration on the nuclear magnetic resonance ~NMR! shielding constants was computed for HF, F2, N2, CO, and HBr. The shielding constants for H, C, N, O, and F nuclei were calculated using sum-over-states density functional perturbation theory ~SOS-DFPT!. Diatomic ro-vibrational states were calculated from a discrete variable representation using Morse potentials and po...

NMR is routinely used as an indispensable research tool in present-day chemical laboratories because a wide variety of parameters can be extracted from the response of an ensemble of nuclear spins to a resonant excitation. Among them, the chemical shift in nuclear magnetic shielding and the electroncoupled nuclear spin-spin coupling are direct measures of the change in chemical environment arou...

geometrical structure, nuclear magnetic resonance (n1,1it) chemical shielding tensors, and chemical shiftsof silicon and carbon nucler are investigated for twn infinite size zigzag and armchair single-walled siliconcarbide nanotabes (sicnts). geometrical structures of sients, sit bonds and bond angles of st and cvertices in both zigzag and armchair nanotubes, indicate that bond lengths are appr...

Although some of the platinum(II/IV) and rhodium(III) chemistry is considered ‘old’ and wellknown, the application of modern multinuclear NMR spectroscopic methods to this chemistry in solution reveals new details about their rich and relevant solution chemistry. In this paper we will briefly illustrate that the highly-sensitive 195 Pt NMR shielding is an excellent probe to explore aspects such...

The spectral parameters of the nuclear magnetic resonance (NMR) spectra are dependent on the chemical environment around the nuclei, making NMR spectroscopy a powerful method for studying molecular structure and dynamics at the atomic level. Conversely, the spectral parameters can be calculated if one knows the molecular structure. The spectral parameter prediction plays a key role in many appl...